Table 1. Summary of actin-activated MgATPase activity and in vitro motility of HMM II-B.
HMMs | Basal MgATPase | Actin-activated MgATPase | IVM | HMM K+-EDTA ATPase | ||
---|---|---|---|---|---|---|
-MLCK | +MLCK | |||||
Vmax | Vmax | KATPase | ||||
s-1 | s-1 | s-1 | μM | μm/s | s-1 | |
II-B0 | < 0.008 | 0.008±0.002 | 0.15±0.02 | 5.8±0.6 | 0.16±0.01 | 0.2 |
II-B2 | < 0.006 | 0.006±0.003 | 0.01±0.003 | 2.8±0.8 | NSM | 0.2 |
II-B0, noninserted HMM II-B; II-B2, inserted HMM II-B with a 21-aa insert; NSM, no significant movement. Basal MgATPase is without actin, but with MLCK. [KCl] = 0 mM.